Tension actuated uncoupler

ABSTRACT

A tension actuated fuel (e.g. gasoline) delivery hose uncoupler is disclosed in which, upon a predetermined tension load being applied to the delivery pump hose, the coupling will automatically uncouple thus releasing one end of the hose which, for example, may remain inserted in the fuel tank of a vehicle driving away from the fuel dispensing pump, and the other portion of the hose which is permanently affixed to the pump. The coupler includes normally closed checkvalves which, upon uncoupling of the coupler, close thereby preventing spillage of fuel. Further, the coupler is adjustable so that it may be calibrated to uncouple at predetermined tension loads. The uncoupler is structured so as to substanially eliminate the effects of fluid (e.g., gasoline) delivery pressure on the tension load required for uncoupling.

CROSS REFERENCE TO A RELATED APPLICATION

This is a continuation-in-part application of U.S. patent applicationSer. No. 619,120, filed June 11, 1984, now abandoned which is acontinuation-in-part of U.S. patent application Ser. No. 465,242, filedFeb. 9, 1983, now abandoned which is a continuation-in-part of U.S.patent application Ser. No. 401,083, filed July 23, 1982, now abandoned.

BACKGROUND OF THE INVENTION

This invention relates primarily to a tension actuated coupler for afuel (e.g. gasoline) pump delivery hose which will permit one portion ofthe hose to be uncoupled upon a tension load of predetermined magnitudebeing applied to the hose thereby to prevent damage to a fuel deliverypump or station. Alternatively, the tension actuated uncoupler of thisinvention may be incorporated in the lines supplying the fuel deliverystation or pump such that if the pump is run into by a vehicle forceablytearing the pump from its moorings, the supply lines will automaticallyuncouple and seal. More specifically, this invention relates to such acoupler in which the hose portions, when uncoupled, are sealed so as toprevent the spillage of gasoline or other liquid fuel. Still further,this uncoupler is adjustable so that it may be calibrated (preferably atthe factory) to accurately uncouple at predetermined load levels suchthat the hose is not uncoupled at unduly low loads, but yet which willbe reliably uncoupled at predetermined tension loads so as to positivelyprevent damage to the fuel delivery pump. Also, this uncoupler is soconstructed so as to substantially eliminate inadvertent uncoupling ofthe uncoupler caused by internal liquid pressure.

In recent years, the advent of self service gasoline retailestablishments has become a major, if not the predominant, manner inwhich gasoline and other petroleum fuels are sold at retail. Becausecustomers utilizing self service gasoline pumps are not experiencedgasoline service station attendants, and because they do this onlyoccasionally and may be unfamiliar with the gasoline pump, itsoperation, and the gasoline service station's procedures for dispensingthe gasoline and for payment, oftentimes a customer will dispense aquantity of gasoline into his vehicle's tank, pay for the gasoline,re-enter his car and begin to drive away from the service station pumpisland before he realizes that he has not removed the gasoline pumpdispensing nozzle from the filler neck of his fuel tank. In manyinstances, the nozzle will pull out of the filler neck of the gasolinetank and fall harmlessly to the ground. However, in certain otherinstances, it is possible to exert exceedingly high tension loads on thefuel delivery hose leading from the delivery pump to the nozzle. Morespecifically, as an automobile drives off, it is possible to exert sucha high force on the delivery hose that either the hose is ripped or tornfrom the pump, or that the delivery pump is torn free of its moorings tothe service station pump island. In either instance, the potentialexists for a significant spillage of volatile liquid fuel. Because ofthe close proximity of electrical power within the gas pump for lightingand the like and because these electrical wires may be ripped from thepump as the pump is pulled from its moorings, electrical sparksoftentimes will ignite any spilled fuel. Of course, with the closeproximity of other vehicles and patrons within the service station, thepotential exists for personal injury to several such persons in theevent such a pump is pulled from its moorings and considerable physicaldamage may result to the service station such that it would be closedfor a considerable length of time for repairs thus representing asignificant economic loss to the operators.

In states which require a vapor recovery system for capturinghydrocarbon (e.g., gasoline) vapors as the vehicle is fueled, it wouldbe necessary for the vapor collection system also to prevent damage tothe fuel dispensing pump in the event the vehicle drives away from thefueling site with the filling and vapor collection systems attached orinserted in the fuel tank filler neck.

These problems have been recognized in the past. Certain safety coderequirements require that the spout for the dispensing nozzle be ofbreakaway construction such that at moderate loads, the spout will pullclear of the nozzle thus preventing excessive loads from being appliedto the pump. However, in actual practice, the fact that pumps areregularly pulled clear of their moorings would indicate that the conceptof the breakaway nozzle does not, in all cases, adequately protectagainst such accidents. Additionally, reference may be made to U.S. Pat.Nos. such as 584,144, 2,048,388, 2,536,702, 3,883,042 and 4,098,438which are in the same general field as the present invention.

For many years, dispensing pumps in gasoline stations and the like havebeen prone to being knocked over by vehicles in instances where thevehicle is errantly driven or is involved in an accident. Typically,dispensing pumps are moored to the service station pump island by meansof bolts or the like and delivery pipes for the fuel from undergroundstorage tanks are coupled to piping within the dispensing pump.Oftentimes, in the event of a collision, the dispensing pump will beripped free of its moorings and the supply lines to the pump will beruptured. Fuel (e.g., gasoline) is typically delivered to the dispensingstation or pump from underground storage tanks by a submersible pump. Inthe event the dispensing pump is ripped free of its moorings and in theevent the submersible pump is in operation, it will be appreciated thatconsiderable quantities of volatile fuel may be expelled from the brokensupply lines. In an effort to limit the amount of fuel that can bedischarged upon a pump being ripped free of its moorings, certain pilotactuated diaphragm valves and other safety devices have been developedwhich block the flow of fuel upon the pump being ripped from itsmoorings. One such pilot actuated diaphragm valve is shown in U.S. Pat.No. 4,284,212. However, these various safety means for blocking the flowof fuel from the ruptured supply lines are complex and add considerablyto the cost of installing the delivery pump.

Clark, U.S. Pat. No. 2,860,893, recognized this long-standing problem ofgasoline dispensing pumps being subject to "pull-away" accidents. Clarkdisclosed a ball detent coupling which broke away under tension, such asduring a pull-away accident.

Recently, an uncoupler of the present invention, substantially identicalto FIG. 7 of the previous U.S. patent application Ser. No. 465,242,filed Feb. 9, 1983, and to FIG. 7 herein, was made and sold underlicense by Emco Wheaton of Conneaut, Ohio. While this uncoupler workedwell for its intended purposes, as stated in the above-mentioned U.S.patent application Ser. No. 465,242, it was found, in actual field use,that the uncoupler would, under very low application of tension loadsthereto, or even under no tension load condition, inexplicably uncouple.It was found that the dispensers on which these uncouplers wereinstalled are dispensing gasoline at pressure levels far above thepressure levels considered to be maximum desirable operating pressures,as set forth in standards established by Underwriters Laboratory (U.L.).Thus, even in view of such prior art uncouplers as disclosed in ScheiwerU.S. Pat. No. 2,536,702, and Clark U.S. Pat. No. 2,860,893, and in viewof the instant inventors' earlier embodiment as disclosed in FIG. 7herein, a need continued for a tension actuated uncoupler which not onlywould reliably uncouple at a predetermined tension load applied thereto,but which was substantially unaffected by variations in fluid pressurelevels therewithin or by fluid pressure levels considerably abovenormally expected operating pressure levels.

Further, in fueling vehicles with liquid propane or liquid natural gasfuels, there has been a need for means that would prevent a spillage offuel in the event the vehicle drove away from the fueling area with thefueling hose still connected to its fuel tank.

In addition, automatic quick coupling kits are available for use onhydraulic systems for farm implements and the like which are connectedto a tractor and which are powered by the hydraulic system on thetractor such that if the implement becomes inadvertently uncoupled fromthe tractor, the hydraulic fittings will automatically andinstantaneously break away. Such fittings are commercially availablefrom the Pioneer Quick Coupling Division of Parker Corporation,Minneapolis, Minn. However, these so-called breakaway hydraulic hosecouplings require brackets to hold the female coupling and thesebreakaway couplings have no means for adjusting the force at which thecouplings will break away or pull apart. Because of this inability toadjust the breakaway force and because of the wide variety of fueldelivery pumps, a single breakaway tension force would not beacceptable.

SUMMARY OF THE INVENTION

Among the several objects and features of this invention will be notedthe provision of a tension actuated uncoupling fitting which may bereadily installed on existing service station fuel delivery pumps andwhich may be adjusted for a particular pump so as to have an uncouplingforce which insures that the fitting uncouples at a predeterminedtension load level so as to prevent damage to the delivery pump on whichit is installed;

The provision of such a tension actuated coupling device which willreliably operate after extended periods of service and under a varietyof adverse weather conditions;

The provision of such a tension actuated uncoupling device which may bereadily retrofitted to existing fuel delivery pumps without substantialmodofication to the pump and which permits the ready replacement of pumpdelivery hoses;

The provision of such a tension actuated uncoupling device which whenuncoupled, instantaneously blocks both the portion of the hose remainingattached to the delivery pump and the portion of the hose attached tothe nozzle so as to prevent the spillage of any substantial amount offuel;

The provision of such a tension actuated uncoupling device which isprotected by a suitable abrasion and impact resistant covering so as toprevent damage to automobiles being serviced and so as to protect thecoupling fitting;

The provision of such a tension actuated uncoupling device which mayalso be installed between the fuel lines within the delivery pump andthe underground fuel delivery line leading from underground supply tanksto the pump island so that in the event a vehicle collides with adelivery pump and rips it free of its moorings to the pump island, theflow of fuel from both the pump and the delivery lines will beinstantaneously blocked;

The provision of such a tension actuated uncoupling device in which thetension force required to uncouple the device is substantiallyunaffected by fluid pressure within the device;

The provision of such a tension actuated uncoupling fitting which is oflightweight and yet rugged construction, which operates reliably, andwhich is economical to manufacture and to use; and

The provision of such an uncoupling device which when it isinadvertantly uncoupled, such as by the driving away of an vehicle withthe fuel delivery nozzle remaining inserted in the filler neck of thevehicle such as to cause an uncoupling action of the uncoupler, the hosesections may be readily coupled together such that the undamaged pumpmay be quickly put into service by the service station operator.

Other objects and features of this invention will be part apparent andin part pointed out hereinafter.

Briefly stated, a tension actuated uncoupling device of this inventionis intended for use in a fuel dispensing system, such as in a servicestation or the like, having a pump for delivering liquid fuel (e.g.,gasoline) via a supply line from a reservoir (such as an undergroundtank) to a fuel dispensing station. This fuel dispensing station(oftentimes referred to as a fuel delivery pump) has a flexible deliveryline or hose with a nozzle at its free end for controlling the deliveryof fuel into the fuel tank of a vehicle. More specifically, theimprovement of this invention comprises means installed in a line (i.e.,in either the supply line or the delivery hose) for uncoupling at leasta portion of the line from another portion of the line and forsubstantially instantaneously blocking the flow of fuel from bothportions of the line upon the uncoupling thereof in the event a tensionload of a predetermined value is applied to the line upon, for example,the vehicle driving away from the pump with the nozzle remaininginserted in the vehicle's fuel tank or upon a vehicle colliding with thedispensing station. The uncoupling means comprises a female quickdisconnect fitting secured to one of the line portions and a male quickdisconnect fitting secured to the other of the line portions with themale fitting being sealably received within the female fitting therebyto permit the flow of fuel through the line. The male and femalefittings each have a substantially similar diameter wetted by the fuelflowing therethrough for substantially eliminating the pressure of thefuel from effecting the predetermined value of the tension forcerequired to uncouple the fittings. The coupler further includesreleasable locking means for securing the male fitting within the femalefitting, this locking means comprising a plurality of detent balls orother locking members spaced from one another around the female memberand being movable radially inwardly and outwardly. A circumferentialgroove is provided in the male member in register with the balls whenthe male and female members are sealably secured together. Further,means is provided on the exterior of the female fitting engageable withthe balls for resiliently biasing the balls inwardly toward a lockingposition in which they are at least in part received in the groove onthe male fitting thereby to prevent the male and female fittings frombeing uncoupled, but yet, upon a tension load in excess of apredetermined value being applied to the line portions, the groove onthe male member exerts a camming action on the balls forcing the ballsradially outwardly thereby to permit the uncoupling of the line portionsat the predetermined tension load.

In another embodiment of the present invention, means is provided forapplying a fluid or hydraulic back pressure against the above-said meansengageable with the balls thereby substantially eliminating the effectof fluid pressure on the tension load required to effect uncoupling.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an automobile in a service stationhaving liquid fuel (gasoline) dispensed into the fuel tank of theautomobile via a conventional fuel dispensing station or pump with atension actuated uncoupling device of the present invention installed inthe fuel delivery hose between the pump and the dispensing nozzle on thefree end of the hose;

FIG. 2 is a view similar to FIG. 1 in which the automobile has drivenaway from the pump island with the delivery hose remaining in the fuelinlet to the automobile's gasoline tank and in which the uncouplingdevice of this invention has been actuated by the application of atension load of predetermined value on the hose permitting uncoupling ofthe hose portions without substantial spillage of fuel and withoutdamage to the delivery pump;

FIG. 3 is an enlarged side elevational view of the coupling device ofthe present invention illustrating a female quick disconnect memberresealably receiving a male disconnect member;

FIG. 4 is a longitudinal cross sectional view of at least a portion ofthe coupling device of the present invention illustrating means forsealably locking the male quick disconnect member within the femalequick disconnect member and further illustrating means for adjustablyvarying the magnitude of the tension force required to be applied to thehose sections thereby to permit uncoupling of the hose sections;

FIG. 5 is a front elevational view of a dispensing station or pumpsecured to a pump island or other foundation and a fuel delivery lineleading from an underground fuel supply tank to the dispensing stationwith a coupling device coupling fuel lines within the dispensing stationto the fuel delivery line;

FIG. 6 is a cross-sectional view of another embodiment of the couplingdevice of the present invention;

FIG. 7 is a cross-sectional view of still another embodiment of theuncoupling device of the present invention;

FIG. 8 is a similar to FIG. 7 of a variation of the uncoupling device ofthe present invention in which the seal between the male and femalefitting is positioned on approximately the same diameter as the maximumwetted diameter of the fittings thereby to substantially eliminate thetendency of pressure forces within the fittings from effecting thetension force required to uncouple the fittings; and

FIG. 9 is also a view similar to FIG. 7 illustrating another means forsubstantially equalizing fluid pressure forces exerted on the fittings.

Corresponding reference characters indicate corresponding partsthroughout the several views of the drawings.

DESCRIPTION OF PREFERRED EMBODIMENTS

Referring now to the drawings, a fuel dispensing system (i.e., a servicestation) is indicated in its entirety by reference character 1. As istypical, the service station includes a number of fuel dispensingstations 3, which are normally referred to as pumps. However, theseso-called fuel pumps oftentimes do not contain a pump therein, butrather are merely a metering and control station. In this disclosure,however, the term gasoline pump will be utilized to refer to thedispensing station 3. As is typical, the gasoline pumps in a servicestation are mounted on a pump island or foundation 5 located on thedriveway of the service station. Each of the gasoline pumps 3 includes acabinet 7 which is anchored to the pump island by bolts 9 (see FIG. 5).

As is conventional, gasoline pump 3 includes a fuel dispensing line orhose, as generally indicated at 11, having a manually operated fueldispensing nozzle 13 on the free end of hose 11 which is selectivelymanually operable by a person dispensing fuel thereby to controloperation of pump 3. Nozzle 13 includes a spout (not shown) which isinserted into the filler neck of the fuel tank of an automobile A (orother vehicle) for the delivery of fuel into the fuel tank of theautomobile. Fuel is delivered to pump 3 by means of a submersible pump15 (see FIG. 5) via an underground fuel delivery line 17 from a tank T.Oftentimes, pump 15 will supply fuel to a plurality of gasoline pumps 3.Pump 3 further includes fuel lines 19 within the pump for providingcommunication between fuel delivery line 17 and fuel dispensing hose 11.

In accordance with this invention, a tension actuated coupler, asgenerally indicated at 21, is provided within fuel dispensing hose 11for permitting the flow of fuel therethrough when coupled and foruncoupling at least one portion 23 of fuel dispensing hose 11 (i.e., theouter portion including nozzle 13) from the other portion 25 of the hoseupon the application of a tension load to the hose of a predeterminedvalue thereby to prevent or minimize damage to gasoline dispensing pump3. Additionally, upon uncoupling of the hose, coupler 21 substantiallyinstantaneously blocks the flow of fuel from both portions 23 and 25 ofthe hose thereby to prevent any substantial spillage of fuel and therebyto minimize fire hazards.

More particularly, fuel dispensing hose 11, intermediate its ends, has aswaged female fitting 27 sealably secured to the first hose portion 23extending from the upper end of pump 3. A female coupling fitting, asgenerally indicated at 29, is sealably threaded into the swaged femalefitting 27. The other half of coupler 21 is constituted by male fitting,as indicated at 31, which is sealably received within female fitting 29when male and female fittings are sealingly coupled together. A threadednipple 33 extends from the end of the male fitting 31 and is received ina swaged female fitting 35, similar to swaged female fitting 27, withthis last-said swaged fitting sealably secured to the second portion 25of fuel dispensing hose 11.

More specifically, female fitting 29 is constituted by a female body 37having a flow passage 39 therethrough with a counterbore 41 in its innerend for receiving the outer portion of male fitting 31. As indicated at43, female body 37 has a plurality of openings 43 therein extendingcircumferentially around the female body with each of these openingsreceiving a respective locking member or detent ball 45. Balls 45 aremovable relative to female body 37 radially inwardly and outwardly withrespect to female body 37 for purposes as will appear.

Female body 37 further includes a check valve member 47 movable betweena closed position (not shown) in which the flow of fuel through centralbore 39 is blocked and an open position (as shown in FIG. 4) in whichfuel may readily flow through coupler 21 from gasoline pump 3 to nozzle13. A check valve spring 49 biases check valve member 47 to its closedposition. Within central bore 39 of female body 37 a snap ring stop 51is provided so as to serve as an abutment for check valve spring 49. Acheck valve seat 53 is formed within central bore 39 and is engagablewith check valve member 47 when the latter is in its closed position toblock the flow of fuel as described above. The outwardly facingshoulder, as indicated at 54, of seat 53 constitutes a limiting abutmentwithin counterbore 41 adapted to engage the outer end of male fitting 31and to prevent inward movement of the male fitting relative to femalefitting 29 beyond a predetermined axial distance (i.e., the location ofshoulder 54).

Male fitting 31 is constituted by a male fitting body 55 having acentral bore 57 extending axially therethrough, the central bore 57 ofmale fitting body 55 being generally coaxial with central bore 39 offemale body 37 when the male fitting is coupled to the female fitting asshown in FIGS. 3 and 4. As indicated at 59, a circumferential detentgroove is provided around the outer end of male fitting body 55generally in register with detent ball openings 43 in female body 37when the male and female fittings 29 and 31 are sealably coupledtogether whereby detent balls 45 may move radially inwardly intoregister with circumferential groove 59 thereby positively preventingwithdrawal of the male fitting from its coupled position within femalefitting 29. As best shown in FIG. 4, circumferential groove 59 hasbeveled sidewalls 60 which constitute cam faces engageable with thedetent balls 43 for cammingly forcing the detent balls radiallyoutwardly upon applying a longitudinal or axial tension load to hoseportions 23 and 25. It will be appreciated that if this radiallyoutwardly camming action of beveled cam faces 60 of circumferentialgroove 59 are of sufficient magnitude so as to forceably move balls 45out of the circumferential groove, female and male fittings 29 and 31will become uncoupled and are free to move axially away from oneanother.

Male fitting 31 has an outer end 61 engageable with shoulder 54 incounterbore 41 of female body 37 when the male and female fittings 29and 31 are sealably coupled together as shown in FIGS. 3 and 4. Further,male fitting 31 includes a normally closed check valve 63 substantiallyidentical in construction with check valve 47 heretofore described. Itwill be noted that both check valve 47 and check valve 63 have portionsthereof which extend out beyond shoulder 54 of female fitting 29 andwhich extend out beyond the outer end 61 of male fitting 31 when themale and female fittings are uncoupled and when the check valves are intheir closed positions. Upon inserting male fitting 31 into counterbore41 of female fitting 29 and upon forcing the fittings into couplingengagement such that detent balls 45 come into register withcircumferential groove 59, the protruding ends of check valve members 47and 63 engage one another and force the check valves from their closedpositions to their open positions against the bias of their respectivecheck valve springs. In this manner, the check valves of the male andfemale fittings are automatically opened upon coupling of coupler 21and, of course, upon uncoupling of the coupler, the check valves willautomatically close thus blocking the flow of fuel therefrom. Inaddition, counterbore 41 includes a seal 64 engageable with the outerend of male fitting body 55 as the latter is inserted into thecounterbore thereby to positively prevent leakage of fuel from thecoupler.

In accordance with this invention, coupler 21 includes means 65engageable with detent balls 45 for biasing the detent balls radiallyinwardly relative to female fitting body 37 and for permitting radialinward and outward movement of the balls relative to the female fittingbody. More specifically, this biasing means 65 is shown to comprise asplit collar, as indicated generally at 67, having a plurality of collarmembers 69 movable independently of one another and engageable with theouter surfaces of respective detent balls 45. Further, means 65 is shownto comprise a circumferential spring 71 engagable with the outer face ofsplit collar 67 for resiliently biasing collar members 69 and the detentballs 45 engageable therewith radially inwardly relative to femalefitting body 37 thereby to maintain the detent balls in engagement withthe base of circumferential groove 59 in male fitting body 55 andthereby to positively maintain male fitting 31 in coupled relation withfemale fitting 29. It will be appreciated that as detent balls 45 arecaused to move radially outwardly relative to female body fitting 37,such as by an outward camming force applied to the detent balls bybeveled cam faces 60 of circumferential groove 59 upon the applicationof an axial tension load to the male and female fittings,circumferential spring 71 will stretch or increase in length therebypermitting collar members 69 and balls 45 to move radially outwardly.

As best shown in FIG. 4, each collar member 69 extends around a portionof the outer surface of female fitting body 37 and has a first contactpoint 73 engagable with the outer surface of its respective detent balls45 and a second contact point 75 engageable with the outer surface offemale fitting body 37, the first and second contact points being spacedaxially from one another. Additionally, collar members 67 have anothercontact point intermediate the first contact point 73 and the secondcontact point 75, this intermediate contact point being constituted by acircumferential groove 77 formed in the outer faces of the collarmembers thereby to constitute a retaining groove for circumferentialspring 71. It will be understood that, during fabrication of collarmembers 69, the location of intermediate groove 77 relative to the firstcontact point 73 (i.e., relative to the point of contact of the splitcollar members on the outer surfaces of its respective detent balls 45)determines the amount of inward biasing force of the circumferentialspring 71 on the detent balls. More specifically, if the location ofintermediate groove 77 is located directly over the point of contact ofthe split collar members 69 on the detent balls, the maximum inwardbiasing force is exerted on the detent balls. However, as the locationof intermediate groove 77 moves axially away from the balls toward thelocation of the second contact point 75, the inward biasing forceexerted on the balls proportionately decreases.

Further, in accordance with this invention, coupler 21 is provided withadjustable means for varying the axial tension load applied to fittings29 and 31 required to permit uncoupling of the male and female fittingssuch that the coupler will break apart upon the application of apredetermined axial tension load thereto. In the coupler describedabove, it will be appreciated that by exchanging one circumferentialspring 71 having a first spring constant for another circumferentialspring having a higher or lower spring constant, the inwardly biasingforces exerted on the detent balls may be selectively varied. Further,by shifting the location of the circumferential groove 77 on the outersurfaces of collar members 69 toward and away from the first contactpoint 73 (i.e., toward or away from the point of contact of the collarmembers on the detent balls), the inwardly resilient biasing force ofthe spring 71 on the detent balls may be varied. Also, by changing theangle of beveled cam surfaces 60 of circumferential groove 59 on malefitting body 55, the outward camming force exerted on the balls by anaxial tension load on the fittings 29 and 31 required for uncouplingthereof may be varied.

Still further in accordance with this invention, it will be understoodthat that circumferential spring 71 may be mounted on an adjustablescrew-type mounting fixture (not shown), similar to a conventional hoseclamp, such that the inward biasing force of the spring may be readilyvaried by adjusting the screw clamping arrangement thereby to increaseor decrease the length of the spring. However, it is believed that it bepreferable that the adjustment of the predetermined break away tensionforce for coupler 21 should only be done "at the factory" such thatfield service personnel and service station attendants will not betempted to change the tension loading on spring 71 as this could causeuncoupling of coupler 21 at abnormally low or high tension forces.

The force at which coupler 21 will reliably uncouple is a matter to bedetermined, depending upon the particular application of coupler 21. Forexample, if coupler 21 is installed in gasoline dispensing hose 11 andif the gasoline pump 3 is of a known design or model, then it can bedetermined what magnitude of tension load can be safely transmitted bythe pump from hose 11 to the mounting of gasoline pump 3 on itsfoundation or pump island 5 without damage to nozzle 13, to gasolinedispensing hose 11 and without damage to the gasoline pump. Preferably,the predetermined axial tension load at which coupler 21 will reliablyuncouple is selected such that the uncoupling force is, at all timesduring normal operation of gasoline pump 3, above the normal tensionloadings usually imposed on the gasoline delivery hose by normaloperations. However, in the event, for example, fuel dispensing nozzle13 remains inserted in the filling neck of the fuel tank of anautomobile A or other vehicle (as shown in FIGS. 1 and 2) and in theevent the driver of the vehicle drives the vehicle away from the pumpisland thus placing an abnormally high axial tension load on thegasoline delivery hose 11, coupler 21 will uncouple thus preventing theapplication of excessive loads on nozzle 13, on fuel delivery hose 11and on gasoline pump 3 so as to minimize or prevent damage thereto.Further, upon uncoupling of the male and female fittings, the checkvalves 47 and 63 thereof will automatically close thus preventing thespillage of any substantial amount of fuel and thus substantiallyreducing any potential fire hazard.

Further in accordance with this invention, coupler 21 may be utilized toconnect the fuel delivery lines 19 within cabinet 7 of gasoline pump 3to the underground fuel delivery lines 17 supplying fuel to gasolinepump 3 from submersible pump 15. Thus, in the event a substantialtipping force would be applied to the gasoline pump, either caused by anautomobile pulling away from the pump island with nozzle 13 remaininginserted in the filler neck of the vehicle's gasoline tank or caused bya collision between the vehicle and the gasoline pump, the pump willpull free of the fuel supply lines 17 and coupler 21 will prevent anysubstantial spillage of fuel. It will be appreciated with pump 15supplying volatile fuel to a plurality of gasoline pumps 13, ininstances where gasoline pump 13 is torn from its mounting on pumpisland 5, pump 15 could continue to deliver substantial quantities ofthe volatile fuel via the fuel delivery line 15 and thus could create asubstantial risk of fire or explosion.

Further, it will be appreciated that with coupler 21 installed on fueldispensing hose 11, the coupler may be utilized to permit the readyexchange of one fuel delivery hose and nozzle assembly with another.Thus, servicing of the nozzles and of the dispensing hoses could bereadily facilitated. Still further, it will be appreciated that thecoupler 21 of the present invention incorporated in a new fueldispensing hose and nozzle assembly can be readily retrofitted toexisting gasoline delivery pumps 3 without substantial modification tothe gasoline pumps. Thus, in a short time, all of the gasoline deliverypumps at a service station could readily be converted to include thecouplers 21 of the present invention.

Also, those skilled in the art will recognize that fluid pressure withincoupler 21 may exert an axial tension load on female fitting 27 and onmale fitting 31 such that upon the fluid pressure within hose 11exceeding a predetermined pressure level, coupler 21 will automaticallyuncouple.

Referring now to FIG. 6, another embodiment of the tension actuatedcoupler of the present invention is shown in detail, as it is installedon the fuel delivery hose 11. In the disclosure of the second embodimentof this tension actuated coupler, the coupler is indicated in itsentirety by reference character 21'. It will be understood thatcorresponding parts for the second embodiment of the coupler having asimilar construction and function as parts heretofore described inregard to coupler 21 will be indicated by "primed" reference numbers andthus the construction and operation of these components or parts ofcoupler 21' will not be described in detail for the sake of brevity.

The primary difference in construction and operation between coupler 21and coupler 21' is the fact that while both of the couplers are tensionactuated devices intended to uncouple hose portions 23 and 27 from oneanother upon the axial tension forces applied to delivery hose 11 or 11'exceeding a predetermined value, coupler 21 operated on the principle ofa camming action being applied to the detent balls 45 by the camsurfaces 60 in circumferential groove 59 of the male fitting member withthese camming forces forcing the detent balls radially outwardly andcausing the split collar members 69 to move radially outwardly againstthe bias of circumferential spring 71. However, in the second embodimentof the coupler 21', a tension force exerted on the hose is reactedthrough a shear member, as generally indicated at 81, carried by femalefitting body 37' such that the shear member will fail and shear at apredetermined axial tension load thereby permitting a collar 83 slidablymounted on the exterior of female body 37' to move axially from aretaining position (as shown in FIG. 6) in which the collar surroundsthe detent balls 45' and positively prevents the detent balls frommoving radially outwardly thus keeping the detent balls engaged withcircumferential groove 59' and thus positively coupling the male andfemale fittings together to a retracted position (i.e., axially shiftedto the right as shown in FIG. 6) and which an enlarged inner diameterportion 85 of collar 83 moves into register with the detent balls thuspermitting the detent balls to move radially outwardly away from themale collar members and thus permitting uncoupling of the hose.

As best shown in FIG. 6, the tension force exerted on slidable collar 83is exerted through a lanyard 87 securely fastened to the collar and tohose portion 25' with a kink or slack portion, as indicated at 89provided, in hose portion 25' such that lanyard 87 transferssubstantially all of the tension forces in the hose to slidable collar83. It will be appreciated that shear member 81 may be made of arelatively easy shearable material, such as lead, brass, or the likewhose shear forces may readily be determined suoh that the shear member81 will fail reliably at a predetermined tension load. Further, once theshear member 81 has failed and once the collar has moved from itsretaining to its released position thus permitting the uncoupling of thehose portions, it will be appreciated that lanyard 87 is so designed asto readily fail under tension forces before any permanent damage may bedone to the fuel dispensing station 3 or to the hoses.

As described above in regard to coupler 21', upon the coupler 21uncoupling, the check valves incorporated within the male and femalefittings will instantaneously close thereby preventing the spillage ofany substantial amount of fuel.

Referring now to FIG. 7, still another embodiment of the tensionactuated uncoupler of the present invention is generally indicated byreference character 21". This other embodiment of the tension actuateduncoupler of the present invention is generally similar in constructionand operation to the tension uncouplers heretofore described and the"double primed" reference characters indicate parts having a similarconstuction and function as parts heretofore disclosed in regard totension actuated uncoupler 21. Thus, the description of the constructionand function of these corresponding parts will not be herein set forthin detail.

Among the primary differences between the tension actuated uncoupler21", as shown in FIG. 7, and tension actuated uncoupler 21, as shown inFIG. 3, is the fact that the means of biasing the securing means ordetent balls 45" inwardly toward their securing position thus holdingmale fitting 31" coupled and sealed within counterbore 41" of femalefitting 29" is shown to comprise a collar 101 slidable axially on theoutside of female body member 37" from a retaining position (as shown inFIG. 7) to a released position (not shown, but to the left of theposition of collar 101 shown in FIG. 7) in which detent balls 45" arefree to move radially outwardly relative to male body member 55" thuspermitting the male and female body members to be uncoupled relative toone another. An outer sleeve 103 is mounted on female body member 37"and encloses slidable collar 101 and permits the collar to move withinthe space between the inner surface of the outer body member 103 and theouter surface of female body member 37". A compression coil spring 105is interposed between the end of slidable collar 101 opposite detentballs 45" and a portion of cover member 103 so as to resiliently biasthe slidable collar toward its securing position in which the slidablecollar holds detent balls 45" in their locking position, i.e., withingroove 57" of male fitting body 55". Further, collar 101 has a cam face107 thereon engageable by the outer surface of detent balls 45". It willbe understood that upon an axial tension force being applied to the malebody member 55" and to the female body member 37", such as upon thelongitudinal stretching of the opposite ends of the fuel line or hoseportions attached thereto, cam surfaces 60" forming at least in partgroove 59" on male body part 55" exerts a force on detent balls 45"which tends to move the detent balls radially outwardly within opening43" of female body member 37" such that the outer faces of the detentballs 45" bear against cam face 107 of slidable collar 101 and exert acomponent of axially directed force on collar 101 which tends to movecollar 101 against the bias of spring 105 thereby to move the collartoward its retracted position and to permit the balls to move out ofengagement with cam surfaces 60" of groove 59" and thereby to permituncoupling of the male and female body members. It will be appreciatedthat the axial force exerted on collar 101 is dependent on the angle ofcam faces 60" and cam face 107 on collar 101. By varying the angles ofthese cam faces, and by changing the spring constant of spring 105, theaxial tension forces exerted on tension uncoupler 21 can be selectivelyvaried so that the tension uncoupler 21" will break apart at apreselected axial load applied thereto.

Further referring to FIG. 7, it will be appreciated that check valvemembers 47" and 61" are slidably each carried by a respective spiderarrangement 109 within the male and female body parts and that thespider members 109 having openings 110 therethrough (not shown) for theflow of fluid through fitting 21" when the fitting is in its coupledposition as shown in FIG. 7. The spider members 109 are fixedly held inplace by means of snap rings 51". Further, it will be appreciated thatcover 103 is fixedly held in place by means of a snap ring 111 which isfitted in place on the exterior of female body fitting 37" and which isreceived in a corresponding circumferential groove therein. Each of thecheck valve members 47" and 61" has a corresponding seal 113 thereonwhich is engagable with the bore 39" of female fitting body 37" and withbore 57" of male body fitting 55" when the check valve members are intheir closed position thereby to positively shut off the flow of fluidthrough the fitting members when the fitting 21 is in its uncoupledposition.

Even more specifically, it will be noted in FIG. 7 that female bodymember 37" has a plurality of apertures or openings 43" therein forreceiving balls 45" and that the side walls 44" defining apertures 43"are tapered such that the apertures diverge or expand in a radiallyoutward manner. With the side walls 44" of apertures 43" taperingoutwardly, balls 45" are free to move radially outwardly upon a tensionload being applied to fitting 21" such that the beveled cam surfaces 60"on male body member 31" cammingly forces the balls 45" outwardly. Itwill be appreciated that by tapering sidewalls 44", as shown in FIG. 7,the sidewalls are not able to exert any appreciable frictional force onballs 45" as the balls are forced radially outwardly within theirrespective openings 43". Further, those skilled in the art willrecognize that upon uncoupling, because of the mechanical advantage ofcam surface 60" on balls 45" and of balls 45" on cam face 107 of collar101, even a relatively small frictional force exerted by side walls 44"on balls 45" will require a substantially greater tension force toeffect uncoupling. Also, because of the number of balls 45" (e.g., 4-8balls), the force required to effect uncoupling may vary considerably,depending on how many balls 45" bear on the walls 44" of apertures 43"and depending on the resistance afforded to each of the balls. Bytapering side walls 44" outwardly, as shown in FIG. 7, the side wallsdiverge away from the radial path of the balls and constitute a ramp onwhich the balls may roll without exerting substantial resistance tooutward movement of the balls, but yet preventing substantial axialmovement of the balls relative to female fitting member 37".

Referring now to FIG. 8, another embodiment of the tension actuateduncoupler of this invention is indicated in its entirety by referencecharacter 21a. Uncoupler 21a is generally similar to uncoupler 21"heretofore described and shown in FIG. 7. Parts of uncoupler 21a havinga corresponding function and construction as do parts of uncoupler 21"are denoted by the suffix "a" on the reference characters. The primarydifference between uncoupler 21a and 21" is that uncoupler 21a includesmeans 150 for substantially eliminating the effect of internal fluidpressure within the uncoupler on the predetermined tension forcerequired to uncouple the uncoupler.

More specifically, uncoupler 21a differs from uncoupler 21" in that theouter end of male fitting 31a is necked down by means of an inwardlytapered shoulder 151a having an axially extending end 153a. Likewise,the female bore 41a of female fitting 31a has an inwardly slopingshoulder 155a having a circumferential groove 157a at the inner endthereof. An o-ring seal 159a is received in groove 157a. O-ring 159a isanalogous to seal 64 shown in FIG. 7, except o-ring 159a is movedradially inwardly such that the wetted and unwetted radii of uncoupler21 are substantially equal. Even more preferably, the wetted andunwetted radii of the uncoupler would be equal thereby to minimize oreven eliminate entirely the tendency of fluid pressure forces acting onthe male and female fittings affecting the tension load applied to theuncoupler so as to result in uncoupling.

As shown in FIG. 8, the wetted radius (or wetted area) of male fitting31a is the radius of central bore 57a, while the unwetted radius (orwetted area) of fitting 31a is the inner radius of O-ring 159a. Thewetted radius of male fitting 31" of FIG. 7 is again the radius ofcentral bore 57", while the unwetted radius (or unwetted area) offitting 31" is the inner radius of O-ring seal 64". As stated above inregard to coupler 21a, as shown in FIG. 8, the wetted and unwetted radiiare substantially equal. However, in contradistinction, it can be seenin FIG. 7 that the unwetted radius (i.e., the inner radius of O-ringseal 64") is substantially larger than the wetted radius (i.e., theradius of central bore 57"). This substantial difference between thewetted and unwetted radii defines an annulus against which fluidpressure acts only in one axial direction so as to exert an unbalancedaxial tension force on fittings 29" and 31" which tends to reduce thetension force required to be applied to the fittings so as to result inuncoupling.

In FIG. 9, still another embodiment of the uncoupler of the presentinvention is indicated in its entirety by reference character 21b, withreference characters having a "b" suffix indicating similar parts havinga construction and function similar to those parts heretofore described.However, uncoupler 21b differs in that it includes means, as indicatedat 200, for hydraulically counterbalancing the effect of fluid pressureexerted on the male and female fittings 31b and 29b, respectively, sothat internal fluid pressure within the uncoupler has substantially noeffect on the tension loads required to result in uncoupling of theuncoupler. More specifically, hydraulic counterbalancing means 200includes a port 201 providing communication between central bore 39b offemale fitting 29b and an annular chamber 202 defined by the outersurface of female body 37b and the inner surface of sleeve 103b.Slidable collar 101b is sealed relative to female fitting body 37b andrelative to sleeve 103b by seals 203b so as to permit axial slidingmovement of collar 101b without leakage of fluid post seals 203b.

In accordance with this invention, the area of collar 101b against whichfluid pressure in chamber 202 acts is substantially equal to the area offittings 29b and 31b against which fluid pressure acts to exert anuncoupling force on the uncoupler. This area of the uncoupler againstwhich fluid pressure acts to exert an uncoupling force on the fittingsis an annulus defined by the difference between the unwetted radius andthe wetted radius, as shown in FIG. 9. Thus, with fluid flowing throughthe fittings, the uncoupling forces exerted on fittings 29b and 31b dueto fluid pressure forces acting on the annulus defined by the differencebetween the wetted and unwetted radii of the fittings tends to forceballs 45b radially outwardly which in turn tends to force collar 101btoward its retracted position (i.e., toward the left, as shown in FIG.9). This uncoupling force is opposed by the hydraulic or fluid pressureforces of the system fluid acting on sleeve 101b. Of course, upon atension load applied to fittings 29b, 31b equal to or greater than thepredetermined uncoupling load, the fittings will uncouple in the mannerheretofore described substantially unaffected by fluid pressure withinthe uncoupler. Additionally, those skilled in the art will appreciatethat a pilot valve (not shown) in communication with chamber 202 couldbe provided to dump fluid pressure from chamber 202 such that fluidpressure acting on fittings 29b, 31b would uncouple the fittings uponthe fluid pressure being above a predetermined pressure level.

Additionally, those skilled in the art will recognize that the tensionactuated couplers of this invention may also have suitable applicationsfor use on the hydraulic systems of various implements, particularlyfarm implements, which permit uncoupling of hydraulic hoses from theimplement to the tractor in the event the implement inadvertantlybecomes unhitched from the tractor thereby to prevent damage to thehydraulic hoses and to prevent the loss of hydraulic fluid. Further,those skilled in the art will recognize that the uncoupler of thisinvention would have application in other fuel dispensing systems, suchas liquefied propane and liquefied natural gas systems. Specifically, ifsuch an uncoupler were used as the dispensing nozzle of a liquefiedpropane system for filling a vehicle tank, the hose would automaticallypull clear of the tank filling coupling upon the automobile driving awayfrom the fuel dispensing pump in the event the attendant or other persondispensing the fuel forgot to disconnect the dispensing hose prior tothe vehicle driving away.

In view of the above, it will be seen that the other objects of thisinvention are achieved and other advantageous results obtained.

As various changes could be made in the above constructions withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

We claim:
 1. Tension actuated uncoupler installable in a line forpermitting the flow of a fluid therethrough when coupled and foruncoupling at least a portion of said line from another portion thereofin the event a tension load above a predetermined limit being applied tosaid line, said uncoupler comprising a female quick disconnect fittingsecured to one of said line portions and a male quick disconnect fittingsecured to the other portion of said line, said male and female fittingseach having a flowpath therethrough which, when said fittings arecoupled, permits the flow of fluid through said line, a plurality ofapertures in said female fitting, a plurality of securing balls carriedby said female fitting, one said ball in a respective aperture, saidballs being engagable with said male fitting for positively holding thefittings together in coupled relation, said balls being movable radiallyinwardly and outwardly relative to said male fitting for holding thefittings together in coupled relation and for permitting uncouplingthereof, respectively, cam means on said male fitting camminglyengagable with said balls, a retainer having cam means and being movableaxially relative to said female fitting from a retaining position inwhich said balls are cammingly engagable with said male fitting and withsaid cam means on said retainer for holding said fittings in coupledrelation and a retracted position permitting said balls to move radiallythereby to permit uncoupling of said fittings, said retainer beingcammingly engaged by said balls upon a tension load being applied tosaid fittngs, and spring means resiliently biasing said retainer inaxial direction toward its retaining position, a seal carried by one ofsaid fittings for sealingly engaging the other fitting upon the fittingsbeing secured together in said coupled relation and upon said fittingsmoving axially into and out of said coupled relation, said seal being solocated with respect to the centerline of said fittings that the crosssectional area of said flowpaths of said fittings are substanially equalto the cross sectional area of seal means so that upon the applicationof axial tension loading to said fittings, said predetermined load limitbeing substantially unaffected by fluid pressure within said uncoupler.2. A tension actuated uncoupler as set forth in claim 1 wherein saidmale fitting has a circumferential groove therein in register with saidopenings, said groove receiving at least a portion of said balls whensaid male and female fittings are coupled together with said ballspositively locking the female and male fittings together in coupledrelation.
 3. A tension actuated uncoupler as set forth in claim 2wherein said circumferential groove in said male fitting has a beveledwall constituting said cam means for cammingly engaging at least aportion of said balls upon application of tension loading to saidfittings thereby to force said balls radially outwardly relative to saidmale and female fittings.
 4. A tension actuated uncoupler as set forthin claim 3 wherein said retainer is a collar slidable axially on theoutside of said female fitting and being engagable with said balls so asto hold said balls in their coupled relation with said male fitting. 5.A tension actuated uncoupler as set forth in claim 4 wherein said springmeans comprising a spring interposed between said female fitting andsaid collar for resiliently resisting axial movement of said collar asthe latter moves from its retaining position to its retracted position.6. A tension actuated uncoupler as set forth in claim 5 wherein saidcollar has a cam face thereon engagable with a radially outward surfaceof said balls, said balls exerting an axial force on said collar therebyto compress said spring and to force movement of said collar from itsretaining position toward its retracted position.
 7. A tension actuateduncoupler as set forth in claim 6 further comprising a cover enclosingsaid collar and said spring.